#!/usr/bin/perl -w

use strict;
use threads;
use threads::shared;
use Thread::Queue;

my $qQueue0 = Thread::Queue->new; 
my $qQueue1 = Thread::Queue->new; 

my $href;
$href = &share({});
$href->{'a'}=1;
$href->{'b'}=2;
$href->{'c'}=3;
$href->{'d'}=4;
print "before enqueue\n";
printKeys($href);
print "\n";
$qQueue0->enqueue($href);
$href = &share({});
$href->{'e'}=5;
$href->{'f'}=6;
$href->{'g'}=7;
$href->{'h'}=8;
print "before enqueue\n";
printKeys($href);
print "\n";
$qQueue0->enqueue($href);
$qQueue0->enqueue(undef);

my $sahr_thread = threads->new(\&sahr_thread, $qQueue0, $qQueue1);
$sahr_thread->join;

while ($href = $qQueue1->dequeue) {
    print "Results\n";
    printKeys($href);
    print "\n";
}

sub printKeys {
    my $loc_href = shift;
    print "KEYS  : ";
    print(($_).' ') foreach (sort keys %{$loc_href});
    print "\nvalues: ";
    print(($$loc_href{$_}).' ') foreach (sort keys %{$loc_href});
    print "\n";
}

sub sahr_thread {
    my ($inqueue, $outqueue) = @_;
    my %inhash;
    my $inhashref;
    my $outhashref;
    while ($inhashref = $inqueue->dequeue) {
        %inhash = %{$inhashref};
        print "within thread - inhash\n";
        printKeys (\%inhash);
        print "\n";
        $outhashref = &share({});
        %$outhashref = (%inhash);
        $outhashref->{z} = 9;
        $outhashref->{y} = 8;
        print "within thread - outhash\n";
        printKeys ($outhashref);
        print "\n";
        $outqueue->enqueue($outhashref);
    }
}
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